1. Field of the Invention
The present invention relates to a semiconductor optical device.
2. Related Background Art
Publication 1 (A. J. Ptak et al., J. Cryst. Growth 251 (2003) 392-398) discloses comparison in crystal quality between GaInNAs semiconductors grown by MBE and MOCVD. The hydrogen concentration of the GaInNAs semiconductor by MOCVD is 1×1019 cm−3 and the hydrogen concentration of the GaInNAs semiconductor by MBE is below detection limit of secondary ion mass spectroscopy analysis.
Publication 2 (Masahiko KONDOW et al., Jpn. J. Appl. Phys. 38 (1999) L1355-L1356) discloses the results of continuous current test of a semiconductor laser having GaInNAs semiconductor grown by MBE. The characteristics of the semiconductor laser are not degraded even after 1000 hour continuous current supply.
Publication 3 (A. Polimeni, et al., Phys. Rev. B 63 (2001) 201304(R)) discloses the effect of the implantation of hydrogen ion to GaInNAs semiconductor grown by MBE. As the concentration of hydrogen is increased in the GaInNAs semiconductor, its bandgap Eg is also increased and the intensity of the photo luminescence is lowered. N-clusters are combined with hydrogen atoms to generate nonradiative centers.
Publication 4 (A. Amore Bonapasta et al., Phys. Rev. B 69 (2004) 115207) discloses the relationship between the formations of N—H bond and N—H2 bond in GaPN and the fermi level thereof. Publication 4 also discloses theoretical analysis of the combination between nitrogen and hydrogen.